Trio sewage treatment plant



FIG. 1 is a perspective view of the trio sewage treatment plant showing my new design from an angle above the article;

FIG. 2 is a perspective view of the trio sewage treatment plant from an angle slightly below the article;

FIG. 3 is a top view;

FIG. 4 is a bottom view;

FIG. 5 is a side view;

FIG. 6 is the other side view;

FIG. 7 is an end view; and,

FIG. 8 is the other end view. 

The ornamental design for a trio sewage treatment plant, as shown and described. 